BI Lighting Mystery: Ceiling is receiving less light than the rest of the room
Well your using Blender internal and not cycles so its not perfectly light emulation. Here are the steps to make it a bit better, first decrease the strength of those lamps 

( set it to 0.001 or so, there is way to much light in the scene currently).

in the world tab:


enable Ambiant Occlusion
enable indirect lightning
set Gather to Approximate


there are some more problems (placing of lights etc) but above should give you a start for this file.